How hard/annoying is it to defeat a perfect, maxed Blissey in a gym?

You can't and never ever have found a high level Blissey anywhere to fight? Really?

Not in all your time?

On topic...congratulations on your Blissey. You are clearly very proud

It's annoying but doable within 30 minutes. RIP

You wont be fighting a perfect IV blissey at max stats unless its fresh in the gym from just being placed or from berrying because of CP decay, and alost most blissey arent (from what ive seen) even maxed level, most always hovering around 2.6-2.8k cp to not demotivate faster

A max perfect blissey really isnt that much harder to defeat than a nonperfect blissey for that reason, speaking as someone with a maxed perfect one and someone who (with a friend) clocked the time to win of a maxed perfect and a maxed nonperfect, there wasnt much time difference.

Fighting Blissey is not hard, just annoying, for me. Personally if I saw a full motivated high level Blissey on a gym, I'll just pass. Congrats on your Blissey but one day this baby will beat yours : )

It takes about 45 seconds to defeat at full motivation and one hyper potion. The IVs of defenders don't make a huge difference, generally it's 1-2 seconds at most. Like TheClurachan said, it takes a bit over 20 minutes with optimal execution to kick out a maxed Blissey through 10 berries, so a fairly annoying deal.

Generally when you see Blissey get wins it's because a lower level or unknowledgeable player is fighting it and using low DPS counters. If they go in with 2k Aggrons they will time out and that will get you a win.

E Z P Z. Machamps and battling it (and the rest of the gym) with 1 or 2 others a piece of cake, regardless of the Iv's or cp. Blissey take down 101.

I have a perfect Blissey and a near perfect Blissey I often drop in my local gyms, both maxed out. I am told by local players they are a *****, but it's obviously doable. I've seen level 25 players take them out at max CP in like 5 minutes.

Take longer to take down than any gym defender, but not necesarily harder if you have a good counter for it.
Just a mater of who has more time and willingness when fighting a GRB feeding trainer. Using a high level Machamp or Hariyama is fast enough to defeat it in case there is GRB involved. I ussually bring 2 Machamp at level 40 just in case.

I do have a hundo Blissey maxed out, and my son's account is different team, so when he tries... he's discouraged after just 1 fight.

The key here is how much you are able to feed with the correct timing. I generally can't afford looking at the game other than when I'm really playing on the street, so I'm done unless the others are feeding. That means, it doesn't matter that I own a hundo maxed Blissey - I can never make the most out of it.

It's going to depend almost entirely on the Attacker - going to answer this from the perspective of a Solo Attacker, not a group. (Group attackers take down Blissey pretty easily when they coordinate properly) Technically a decent Solo Attacker should be able to take down that Blissey, even with the Defender GR'ing it, within 30min.

However, even though I've got 2 Perfect Level 40 C/DP Machamps, I haven't been able to do it reliably because my phone lags and has a habit of losing the GPS signal for Pokémon Go every second or third time I get to the Party Selection screen, which pauses it for another 5-10 seconds. And my phone seems to be incapable of reliably dodging, so I'm generally losing 1 of those Machamps every other battle because I don't make the effort to dodge (don't know if it's my phone or my provider, but I've literally hopped to the other side of the screen when a Hyperbeam is coming, and STILL been hit by it full force) and need to heal up - which also seems to pause for 5-10 seconds per healing session. Meaning that I'm generally looking at 3min per battle vs a Blissey, so taking it down solo is tough for me.

So it's going to be obnoxious AND difficult to take down for a Solo player, just not impossible.